These life-sustaining bodies of water are slowly becoming the vectors of a plastic menace, the deleterious impacts of which on marine ecosystems are visible and far-reaching. According to marine protection organisation Ocean Conservancy, more than 800 species of marine wildlife, including seabirds and sea turtles, have been documented to have been affected by plastic debris.

These animals suffer by either becoming entangled in plastic waste or ingesting it, with some 25 per cent of fish and shellfish purchased in markets found to contain plastics in their guts, while research has shown that the presence of plastics in marine organisms could affect their brain functioning and reproductive systems.

But how does all this plastic enter the world’s waterways? A study by the Helmholtz Centre for Environmental Research (HCER) published last month (17 October) has revealed that somewhere between 88-92 per cent of all plastic entering the marine environment comes from ten rivers in Africa and Asia, with eight out of the ten rivers located in South and Southeast Asia (including the Yangtze, the Ganges and the Yellow River) - a region experiencing rapid economic development, urbanisation and population growth.

The combined pressure of these phenomena leads to the population's needs outstripping the capacity supplied by the infrastructure, with waste management capacities lagging behind those found in Western nations.

As Nick Mallos, Director of Ocean Conservancy’s Trash Free Seas Programme, says: “The world’s major cities are concentrated along rivers and coastlines, and where there’s more people, there’s more plastic—from single-use items like take out containers and food packaging to toys, car parts, furniture and everything in between. In many of the countries through which these rivers flow, population growth and consumption is vastly outpacing waste collection; so large amounts of plastic end up in these major river systems and ultimately the ocean.

Pollution in the Pasig River in Manila

Photo: Greenpeace

“In developing countries with rapidly growing economies, consumerism and waste generation have outpaced waste collection and recycling. And while uncollected waste contributes the majority of the problem, trash also enters the environment post-collection in many of these economies.”

Within these developing economies, leakage pathways of plastic waste vary across regions. This depends on population levels, the amount of waste generated per square kilometre, the degree to which waste is aggregated at dump sites, existing investment in waste systems and infrastructure, and local incentive policies.

The study found that in the top five plastic-polluting countries - China, Indonesia, the Philippines, Thailand and Vietnam - formal recycling and waste collection systems are underdeveloped at best, and non-existent at worst, with informal systems widespread.

Waste-picking, where individuals - often from marginal communities - focus on high-value plastics such as PET to pass on to recyclers, leaving low-value plastics such as film and composites in the unregulated waste dumps where they find them, providing the opportunity for it to leak into the ocean.

Public perceptions

This may come as a shock to many in the West. Concern for the levels of plastics in the marine environment has become almost ubiquitous in the Western nations in recent times and in the UK in particular. Environment Secretary Michael Gove announced a ban on plastic microbeads in wash-off cosmetics from the start of 2018, while the UK appears to be moving closer to the implementation of a bottle deposit return scheme in a bid to tackle the country’s blight of plastic litter.

In light of this high-profile concern for our oceans emanating from government, the public could be forgiven for thinking that Western nations would be the biggest contributors of plastic marine waste.

Indeed, it appears that the UK public vastly overestimates the direct contribution of the West to marine plastic pollution. Forty nine per cent of respondents to a recent British Plastics Federation (BPF)-funded YouGov poll believe that the US and Europe contributed more than 50 per cent of total marine plastic pollution, when in fact both regions combined directly contribute as little as two per cent of the total plastic tonnage in the marine environment.

Commenting on the findings, BPF Head of Public and Industrial Affairs Francisco Morcillo stated: “The BPF is extremely concerned about the presence of plastics in the seas: it simply should not be there. We are working closely with our members to further increase recycling rates and encouraging best-practice in manufacturing facilities to minimise the UK’s marine litter footprint. We are also supporting various projects to educate consumers about the environmental impact of littering.”

Morcillo added: “Although the UK’s contribution to this issue is lower than people think, everyone must play a part in preventing plastic from ending up in our environment. This research highlights the need to continue to educate people about this issue so that collectively we can develop and support the most appropriate and effective solutions, remembering that some countries still do not have the waste and recycling infrastructures we take for granted in the West.”

At first glance, it would appear that the impact of Western nations’ activities has been overblown. However, these figures should not be taken as an excuse for developed nations to shift the blame. It would be remiss to think that all plastics entering the the marine environment from developing nations come from native companies or manufacturers.

In a time of increasing globalisation, companies with their headquarters in developed nations often locate their manufacturing operations in developing countries or market their plastic products in these countries, where it is well-known that their waste management systems are inadequate to capture much of the plastic waste produced by these products. The issue of marine plastic pollution is a global issue and requires the co-operation of all nations to tackle it effectively.

What can we do?

So, as consensus over the need to tackle ocean plastics pollution continues to build, what can be done to stem the flow of plastic pollution into our oceans?

Schmidt et al.’s study suggests that, if the global community comes together to act in a unified manner, by reducing the total plastic loads in the 10 top-ranked rivers by 50 per cent, the total river-based plastic load borne out to sea could be reduced by 45 per cent. This can be achieved by improvements to waste management infrastructure in low and middle-income countries.

In terms of waste collection, it says that collection rates must be pushed beyond 80 per cent in countries where waste systems are underdeveloped, while in high-collection countries, waste leakage must be reduced to about one per cent. Ocean Conservancy has already made strides towards addressing this issue. It established the Trash Free Seas Alliance in 2012 to unite global industry leaders with conservation groups and scientists to drive innovative design and invest in waste management and recycling solutions where they’re needed most, recently setting up a $150-million (£113 million) funding mechanism to achieve that very aim.

Ten per cent of the litter found in the Thames consists of plastic bottles. Most of that will find its way to the sea

Photo: Thames21

Meanwhile, Barry Turner, the Director of Plastics and Flexible Packaging Group at the BPF, points to a need to continue to keep the issue firmly in the public consciousness. “Part of the solution to marine litter is raising public awareness, stopping littering and making it as easy as possible for people to recycle the packaging that protects their products,” he said.

“Clearly, when it comes to recycling ‘on the go’, most favour better provision of recycling bins in public places, and we will continue working with industry, government bodies and wider stakeholders to understand how this can be done.”

On the part of the private sector, progress can be made through designing recyclability into product packaging at the design stage, while strong end-markets should be established to increase the demand for recycled content, which individuals can help bring to fruition through expressing preferences for products with high recycled content.

Finally, Mallos reiterates the global responsibility for dealing with marine plastic pollution: “The problem of ocean plastic is broad and complex and no single entity can tackle it alone - we all have a role to play. Many governments, including in Southeast Asia from where much ocean plastic originates, are taking the problem very seriously and putting forth solutions, but it will take a collective effort that includes the private sector, NGOs, and the public to stem the tide of ocean trash.”

It is clear that much must be done to effectively tackle the unsustainable heaps of plastic pollution entering our oceans every year, but any lasting and visible change will only come with global co-operation, getting everybody to row in the same direction to ensure our hopes of a plastic-free ocean don’t end up all at sea.

The European Commission has proposed a full ban on some of the most commonly used and littered disposable plastic products in Europe, including single-use cutlery, plates, drinks stirrers, straws, cotton buds and sticks for balloons.

A two-month expedition to study the ‘plastisphere’ of the Mediterranean Sea departed from the coast of Italy on Thursday, as scientists seek to study how the alarming formation of a plastic-based marine ecosystem will affect the sea and humans.

Parliament’s Environmental Audit Committee has released its final report from its inquiry into the sustainability of the fashion industry, calling for sweeping changes to improve working conditions and reduce the amount of waste produced in the supply chain.